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                                    EXHIBIT 10.56 
                              SEPARATION AGREEMENT DATED
                                  DECEMBER 18, 1996 
                     BETWEEN THE COMPANY AND GILBERT W. CARNATHAN


December 18, 1996


Gilbert W. Carnathan
23 Minturn Avenue
Broomfield,  CO  80020


Dear Chip:

Cortech, Inc. ("Cortech" or the "Company") has accepted your resignation as 
an officer and, prospectively, as an employee of the Company effective 
December 31, 1996.  As a consequence of, and contingent upon, your accepting 
the terms specified  in the attached legal release by returning the signed, 
notarized release no later than January 8, 1997, the Company wishes to 
continue to receive your services and to provide compensation and certain 
other benefits in consideration of such services, as follows:

CONTINUED SERVICE AS EMPLOYEE OR CONSULTANT
You shall continue to serve as an employee of the Company and shall provide 
services to the Company, in any area of your expertise, as requested by the 
Company's management, at such times and places as reasonably requested.  
Except as otherwise contemplated herein, you shall be available to provide 
such services on an as-needed basis for up to ten (10) hours per week until 
March 31, 1997, and for up to two days per month from April 1, 1997, to 
September 30, 1997.

Your status as an employee will terminate, and thereafter you shall have the 
status of a consultant to the Company (i) if you enter another employment or 
consulting relationship that employs you more than 20 hours per week or 
provides you with health insurance benefits, (ii) on March 31, 1997 or (iii) 
upon receipt from the Company of notice of conversion of your status from 
that of an employee to that of a non-employee consultant, whichever shall 
first occur.  Your status as non-employee consultant will end September 30, 
1997.

It is agreed that you will perform work for the Company's benefit.  You 
hereby assign to the Company all rights to all materials, inventions, 
techniques, processes and the like, developed in the course of this 
Agreement.  You also agree to cooperate as reasonably necessary to assist the 
Company in the perfection of such assignment.  You acknowledge your 
obligation to refrain from unauthorized use or disclosure of the Company's 
confidential or proprietary business information and materials, both during 
the term of this Agreement and after its termination.  Throughout the 
consulting period, you will not, without obtaining the Company's prior 
written approval, directly or indirectly engage or prepare to engage in any 
activity in competition with the Company, accept employment or provide 
services to, or establish a business relationship with a business or 
individual engaged in or preparing to engage in competition with the Company.

COMPENSATION
You shall receive as compensation continuation of your salary at the level in 
effect immediately preceding your resignation ("Salary") until September 30, 
1997, paid on the Company's regular payroll dates.  As required by law, all 
payments will be subject to standard withholding for social security and tax 
purposes.

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                              EXHIBIT 10.56 (CONTINUED)


Since your required working hours will be reduced compared to your customary 
schedule, Cortech will make no additional payment to you for any accrued but 
unused vacation.

EQUITY COMPENSATION
Your stock options will continue to vest during periods in which you continue 
to be employed by the Company or serve as a consultant as provided hereunder, 
on their normal vesting schedule through September 30, 1997.  Therefore, all 
options that are exercisable as of September 30, 1997, will be modified to 
allow exercise until the earlier of their expiration or June 30, 1998.  To 
the extent any options must be amended to effect the foregoing, the Company 
agrees to do so.  You understand that any such amendment will cause an 
Incentive Stock Option to become a Nonstatutory Stock Option.

HEALTH INSURANCE
Your normal coverage under the Company's health insurance plans will 
terminate on December 31, 1996.  You will be eligible to continue your health 
benefits under federal COBRA law for up to 18 months thereafter.  Cortech 
will pay for this benefit until the earlier of September 30, 1997, or the 
date upon which you become covered by another plan.

COMPLETE AGREEMENT
This letter agreement constitutes the complete, final and exclusive 
embodiment of the entire agreement between you and the Company with respect 
to the terms and conditions of the consulting relationship.  In no way does 
this agreement affect your obligations under the Invention and Trade Secret 
Agreement signed by you on December 18, 1996, attached hereto and 
incorporated by reference.  The Company's obligations hereunder are 
contingent upon you complying with all obligations specified in this 
Invention and Trade Secret Agreement.  

You agree by your acceptance of this agreement that as of December 31, 1996, 
you are no longer eligible for benefits under Cortech's  Executive Officers' 
Severance Benefit Plan.  

This agreement is entered into without relying upon any promise, warranty or 
representation, written or oral, other than those expressly contained in this 
letter agreement, and it supersedes any other such promises, warranties, 
representations or agreements.  It may not be amended or modified except by a 
written instrument signed by both you and a duly authorized officer of the 
Company.  This letter agreement shall be construed and interpreted in 
accordance with the laws of the State of Colorado.  If any provision of this 
letter agreement is determined to be invalid or unenforceable, in whole or in 
part, this determination will not affect any other provision of this letter 
agreement. A failure of either you or the Company to enforce at any time, or 
for any period of time, the provisions of this letter agreement shall not be 
construed to be a waiver of such provisions or of your right or the right of 
the Company to enforce each and every such provision.

If you choose to contract with the Company under the terms described above, 
please indicate your acceptance by signing below.  Please return the signed 
agreements to me. 

Sincerely,                             ACCEPTED AND AGREED: 

Kenneth R. Lynn
Chief Executive Officer                Gilbert W. Carnathan  /  Date


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